The present invention relates to an apparatus and method for reducing the symptoms and occurrences of muscle fatigue in a seat occupant and, more particularly, to an apparatus and method for adjusting the position of a supporting element in a seat.
Persons who have to remain seated for relatively long periods of time develop symptoms of fatigue and disturbed circulation, which as a whole have a negative effect on their well-being, concentration, and performance. In the case of relatively long automobile trips in particular, this is undesirable in terms of road safety. In fact it is recommended that people take rest breaks and engage in physical exercises every now and then, but this cannot always be done, for example in stop light-controlled traffic, and finally it is not advisable to stop in the dark at freeway parking areas.
A primary contributor to muscle fatigue in sedentary individuals is the build-up of lactic acid within the muscle fibers and surrounding tissues. Additionally, an individual's posture gradually slumps during prolonged periods of sitting thereby changing the curvature of the person's spine. While the prior art has recognized that some relief from back pain is provided by manipulating the curvature of a seat occupant's spine, the art has yet to identify and capitalize on the benefits of preventing and dissipating lactic acid build-up. In this regard, the present invention provides for repeated movement of the spinal area and muscle tissues in small increments to create a pumping action that increases blood circulation through the muscle fibers and prevents lactic acid build-up. The periodic displacement of the spine and muscle tissues need not be of such a magnitude as to be readily perceptible by the seat occupant. In fact, small movements of a lumbar supporting element that are barely perceptible to a seat occupant and that occur at regular intervals have been found to be particularly effective at preventing the build-up of lactic acid within muscle tissues thereby virtually eliminating muscle fatigue during prolonged periods of sitting.
As indicated above, there are many seats familiar to the art that attempt to address the occurrence of, and symptoms related to, muscle fatigue and disturbed circulation. More particularly, with respect to motor-vehicle seats, massaging elements, hand-driven or motor-driven arching elements adjustable in height and degree of curvature, and automatically or manually adjustable fluid inflatable bellows have been suggested to reduce muscle fatigue during prolonged periods of sitting. However, each of these purported solutions fail to adequately alleviate muscle fatigue, give rise to undesirable effects on the seat occupant, or have other characteristics that have prevented their widespread acceptance.
More particularly, the vibrating or massaging mechanisms known in the art, while being effective to a certain degree, are directed at relieving the muscle fatigue perceived by the seat occupant rather than the build up of lactic acid in the muscle that contributes to the fatiguing of the muscle itself. Additionally, vibrating mechanisms often transmit vibrations to other parts of the motor vehicle and give rise to unwelcome secondary effects.
The adjustable arching supporting elements known in the art are generally mechanical or motor driven apparatuses positionable according to the preference of the seat occupant. Such manually actuated systems fail to provide the repetitive and specifically controlled positioning features of the present invention that have been found to be particularly effective at reducing or eliminating lactic acid build-up and muscle fatigue. Finally, bellows or inflatable bag type elements have not proven to have sufficient fatigue strength to withstand the repeated adjustments necessary over the warranty period insisted upon by seat manufacturers.
Accordingly, it is an object of the present invention to provide an apparatus and method for adjusting the position of a supporting element within a seat according to a specific cycle to relieve muscle fatigue of the seat occupant.
A further object of the present invention is to provide a supporting element and drive assembly having a controller adapted to selectively position the supporting element according to a predetermined sequence.
It is another object of the present invention to provide a drive assembly having a controller that periodically and repeatedly displaces the supporting element an incremental distance that is barely perceivable by the seat occupant.
It is yet a further object of the present invention to provide a method for adjusting the position of a supporting element in a seat in the manner described above.